DepthBufferRasterizerSSEMT.cpp

//--------------------------------------------------------------------------------------
// Copyright 2011 Intel Corporation
// All Rights Reserved
//
// Permission is granted to use, copy, distribute and prepare derivative works of this
// software for any purpose and without fee, provided, that the above copyright notice
// and this statement appear in all copies.  Intel makes no representations about the
// suitability of this software for any purpose.  THIS SOFTWARE IS PROVIDED "AS IS."
// INTEL SPECIFICALLY DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, AND ALL LIABILITY,
// INCLUDING CONSEQUENTIAL AND OTHER INDIRECT DAMAGES, FOR THE USE OF THIS SOFTWARE,
// INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PROPRIETARY RIGHTS, AND INCLUDING THE
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  Intel does not
// assume any responsibility for any errors which may appear in this software nor any
// responsibility to update it.
//
//--------------------------------------------------------------------------------------

#include "DepthBufferRasterizerSSEMT.h"

DepthBufferRasterizerSSEMT::DepthBufferRasterizerSSEMT()
	: DepthBufferRasterizerSSE()
{
	int size = SCREENH_IN_TILES * SCREENW_IN_TILES *  NUM_XFORMVERTS_TASKS;
	mpBin = new UINT[size * MAX_TRIS_IN_BIN_MT];
	mpBinModel = new USHORT[size * MAX_TRIS_IN_BIN_MT];
	mpBinMesh = new USHORT[size * MAX_TRIS_IN_BIN_MT];
	mpNumTrisInBin = new USHORT[size];
}

DepthBufferRasterizerSSEMT::~DepthBufferRasterizerSSEMT()
{
	SAFE_DELETE_ARRAY(mpBin);
	SAFE_DELETE_ARRAY(mpBinModel);
	SAFE_DELETE_ARRAY(mpBinMesh);
	SAFE_DELETE_ARRAY(mpNumTrisInBin);
}

//-------------------------------------------------------------------------------
// Create tasks to determine if the occluder model is within the viewing frustum 
//-------------------------------------------------------------------------------
void DepthBufferRasterizerSSEMT::IsVisible(CPUTCamera* pCamera)
{
	mpCamera = pCamera;
	
	gTaskMgr.CreateTaskSet(&DepthBufferRasterizerSSEMT::IsVisible, this, mNumModels1, NULL, 0, "Is Visible", &mIsVisible);
	// Wait for the task set
	gTaskMgr.WaitForSet(mIsVisible);
	// Release the task set
	gTaskMgr.ReleaseHandle(mIsVisible);
	mIsVisible = TASKSETHANDLE_INVALID;
	
}

void DepthBufferRasterizerSSEMT::IsVisible(VOID *taskData, INT context, UINT taskId, UINT taskCount)
{
	DepthBufferRasterizerSSEMT *pSOCSSE =  (DepthBufferRasterizerSSEMT*)taskData;
	pSOCSSE->IsVisible(taskId, taskCount);
}

//------------------------------------------------------------
// * Determine if the occluder model is inside view frustum
//------------------------------------------------------------
void DepthBufferRasterizerSSEMT::IsVisible(UINT taskId, UINT taskCount)
{
	mpTransformedModels1[taskId].IsVisible(mpCamera);
}

//------------------------------------------------------------------------------
// Create NUM_XFORMVERTS_TASKS to:
// * Transform the occluder models on the CPU
// * Bin the occluder triangles into tiles that the frame buffer is divided into
// * Rasterize the occluder triangles to the CPU depth buffer
//-------------------------------------------------------------------------------
void DepthBufferRasterizerSSEMT::TransformModelsAndRasterizeToDepthBuffer()
{
	mRasterizeTimer.StartTimer();
	
	gTaskMgr.CreateTaskSet(&DepthBufferRasterizerSSEMT::TransformMeshes, this, NUM_XFORMVERTS_TASKS, NULL, 0, "Xform Vertices", &mXformMesh);

	gTaskMgr.CreateTaskSet(&DepthBufferRasterizerSSEMT::BinTransformedMeshes, this, NUM_XFORMVERTS_TASKS, &mXformMesh, 1, "Bin Meshes", &mBinMesh);
	
	gTaskMgr.CreateTaskSet(&DepthBufferRasterizerSSEMT::RasterizeBinnedTrianglesToDepthBuffer, this, NUM_TILES, &mBinMesh, 1, "Raster Tris to DB", &mRasterize);	

	// Wait for the task set
	gTaskMgr.WaitForSet(mRasterize);
	// Release the task set
	gTaskMgr.ReleaseHandle(mXformMesh);
	gTaskMgr.ReleaseHandle(mBinMesh);
	gTaskMgr.ReleaseHandle(mRasterize);
	mXformMesh = mBinMesh = mRasterize = TASKSETHANDLE_INVALID;

	mRasterizeTime[mTimeCounter++] = mRasterizeTimer.StopTimer();
	mTimeCounter = mTimeCounter >= AVG_COUNTER ? 0 : mTimeCounter;

	mNumRasterized = 0;
	for(UINT i = 0; i < mNumModels1; i++)
	{
		mNumRasterized += mpTransformedModels1[i].IsRasterized2DB() ? 1 : 0;
	}
}

void DepthBufferRasterizerSSEMT::TransformMeshes(VOID* taskData, INT context, UINT taskId, UINT taskCount)
{
	DepthBufferRasterizerSSEMT *pSOCSSE =  (DepthBufferRasterizerSSEMT*)taskData;
	pSOCSSE->TransformMeshes(taskId, taskCount);
}

//------------------------------------------------------------------------------------------------------------
// This function combines the vertices of all the occluder models in the scene and processes the models/meshes 
// that contain the task's triangle range. It trsanform the occluder vertices once every frame
//------------------------------------------------------------------------------------------------------------
void DepthBufferRasterizerSSEMT::TransformMeshes(UINT taskId, UINT taskCount)
{
	UINT verticesPerTask  = mNumVertices1/taskCount;
	verticesPerTask		  = (mNumVertices1 % taskCount) > 0 ? verticesPerTask + 1 : verticesPerTask;
	UINT startIndex		  = taskId * verticesPerTask;
	//UINT endIndex		  = taskId == NUM_XFORMVERTS_TASKS - 1 ? mNumVertices1 : startIndex + verticesPerTask;

	UINT remainingVerticesPerTask = verticesPerTask;

	// Now, process all of the surfaces that contain this task's triangle range.
	UINT runningVertexCount = 0;
	for(UINT ss = 0; ss < mNumModels1; ss++)
    {
		UINT thisSurfaceVertexCount = mpTransformedModels1[ss].GetNumVertices();
        
        UINT newRunningVertexCount = runningVertexCount + thisSurfaceVertexCount;
        if( newRunningVertexCount < startIndex )
        {
            // We haven't reached the first surface in our range yet.  Skip to the next surface.
            runningVertexCount = newRunningVertexCount;
            continue;
        }

        // If we got this far, then we need to process this surface.
        UINT thisSurfaceStartIndex = max( 0, (int)startIndex - (int)runningVertexCount );
        UINT thisSurfaceEndIndex   = min( thisSurfaceStartIndex + remainingVerticesPerTask, thisSurfaceVertexCount) - 1;

		mpTransformedModels1[ss].TransformMeshes(mViewMatrix, mProjMatrix, thisSurfaceStartIndex, thisSurfaceEndIndex, mpCamera);

		remainingVerticesPerTask -= (thisSurfaceEndIndex + 1 - thisSurfaceStartIndex);
        if( remainingVerticesPerTask <= 0 ) break;

		runningVertexCount = newRunningVertexCount;
    }
}

void DepthBufferRasterizerSSEMT::BinTransformedMeshes(VOID* taskData, INT context, UINT taskId, UINT taskCount)
{
	DepthBufferRasterizerSSEMT* sample =  (DepthBufferRasterizerSSEMT*)taskData;
	sample->BinTransformedMeshes(taskId, taskCount);
}

//--------------------------------------------------------------------------------------
// This function combines the triangles of all the occluder models in the scene and processes 
// the models/meshes that contain the task's triangle range. It bins the occluder triangles 
// into tiles once every frame
//--------------------------------------------------------------------------------------
void DepthBufferRasterizerSSEMT::BinTransformedMeshes(UINT taskId, UINT taskCount)
{
	// Reset the bin count.  Note the data layout makes this traversal a bit awkward.
    // We can't just use memset() because the last array index isn't what's varying.
    // However, this should make the real use of this structure go faster.
	for(UINT yy = 0; yy < SCREENH_IN_TILES; yy++)
    {
		UINT offset = YOFFSET1_MT * yy;
        for(UINT xx = 0; xx < SCREENW_IN_TILES; xx++)
        {
			UINT index = offset + (XOFFSET1_MT * xx) + taskId;
            mpNumTrisInBin[index] = 0;
	    }
    }

	// Making sure that the #of Tris in each task (except the last one) is a multiple of 4 
	UINT trianglesPerTask  = (mNumTriangles1 + taskCount - 1)/taskCount;
	trianglesPerTask      += (trianglesPerTask % SSE) != 0 ? SSE - (trianglesPerTask % SSE) : 0;
	
	UINT startIndex		   = taskId * trianglesPerTask;
	
	UINT remainingTrianglesPerTask = trianglesPerTask;

	// Now, process all of the surfaces that contain this task's triangle range.
	UINT runningTriangleCount = 0;
	for(UINT ss = 0; ss < mNumModels1; ss++)
    {
		UINT thisSurfaceTriangleCount = mpTransformedModels1[ss].GetNumTriangles();
        
        UINT newRunningTriangleCount = runningTriangleCount + thisSurfaceTriangleCount;
        if( newRunningTriangleCount < startIndex )
        {
            // We haven't reached the first surface in our range yet.  Skip to the next surface.
            runningTriangleCount = newRunningTriangleCount;
            continue;
        }

        // If we got this far, then we need to process this surface.
        UINT thisSurfaceStartIndex = max( 0, (int)startIndex - (int)runningTriangleCount );
        UINT thisSurfaceEndIndex   = min( thisSurfaceStartIndex + remainingTrianglesPerTask, thisSurfaceTriangleCount) - 1;

       	mpTransformedModels1[ss].BinTransformedTrianglesMT(taskId, ss, thisSurfaceStartIndex, thisSurfaceEndIndex, mpBin, mpBinModel, mpBinMesh, mpNumTrisInBin);

		remainingTrianglesPerTask -= ( thisSurfaceEndIndex + 1 - thisSurfaceStartIndex);
        if( remainingTrianglesPerTask <= 0 ) break;
				
		runningTriangleCount = newRunningTriangleCount;
    }
}

void DepthBufferRasterizerSSEMT::RasterizeBinnedTrianglesToDepthBuffer(VOID* taskData, INT context, UINT taskId, UINT taskCount)
{
	DepthBufferRasterizerSSEMT* sample =  (DepthBufferRasterizerSSEMT*)taskData;
	sample->RasterizeBinnedTrianglesToDepthBuffer(taskId, taskCount);
}

//-------------------------------------------------------------------------------
// For each tile go through all the bins and process all the triangles in it.
// Rasterize each triangle to the CPU depth buffer. 
//-------------------------------------------------------------------------------
void DepthBufferRasterizerSSEMT::RasterizeBinnedTrianglesToDepthBuffer(UINT taskId, UINT taskCount)
{
	// Set DAZ and FZ MXCSR bits to flush denormals to zero (i.e., make it faster)
	// Denormal are zero (DAZ) is bit 6 and Flush to zero (FZ) is bit 15. 
	// so to enable the two to have to set bits 6 and 15 which 1000 0000 0100 0000 = 0x8040
	_mm_setcsr( _mm_getcsr() | 0x8040 );

	VecS32 colOffset(0, 1, 0, 1);
	VecS32 rowOffset(0, 0, 1, 1);

	float* pDepthBuffer = (float*)mpRenderTargetPixels; 

	// Based on TaskId determine which tile to process
	UINT screenWidthInTiles = SCREENW/TILE_WIDTH_IN_PIXELS;
    UINT tileX = taskId % screenWidthInTiles;
    UINT tileY = taskId / screenWidthInTiles;

    int tileStartX = tileX * TILE_WIDTH_IN_PIXELS;
	int tileEndX   = tileStartX + TILE_WIDTH_IN_PIXELS;
	
	int tileStartY = tileY * TILE_HEIGHT_IN_PIXELS;
	int tileEndY   = tileStartY + TILE_HEIGHT_IN_PIXELS;

	UINT bin = 0;
	UINT binIndex = 0;
	UINT offset1 = YOFFSET1_MT * tileY + XOFFSET1_MT * tileX;
	UINT offset2 = YOFFSET2_MT * tileY + XOFFSET2_MT * tileX;
	UINT numTrisInBin = mpNumTrisInBin[offset1 + bin];

	vFloat4 xformedPos[3];
	bool done = false;
	bool allBinsEmpty = true;
	mNumRasterizedTris[taskId] = numTrisInBin;
	while(!done)
	{
		// Loop through all the bins and process the 4 binned traingles at a time
		UINT ii;
		int numSimdTris = 0;
		for(ii = 0; ii < SSE; ii++)
		{
			while(numTrisInBin <= 0)
			{
				 // This bin is empty.  Move to next bin.
				if(++bin >= NUM_XFORMVERTS_TASKS)
				{
					break;
				}
				numTrisInBin = mpNumTrisInBin[offset1 + bin];
				mNumRasterizedTris[taskId] += numTrisInBin;
				binIndex = 0;
			}
			if(!numTrisInBin)
			{
				 break; // No more tris in the bins
			}
			USHORT modelId = mpBinModel[offset2 + bin * MAX_TRIS_IN_BIN_MT + binIndex];
			USHORT meshId = mpBinMesh[offset2 + bin * MAX_TRIS_IN_BIN_MT + binIndex];
			UINT triIdx = mpBin[offset2 + bin * MAX_TRIS_IN_BIN_MT + binIndex];
			mpTransformedModels1[modelId].Gather((float*)&xformedPos, meshId, triIdx, ii);
			allBinsEmpty = false;
			numSimdTris++; 

			++binIndex;
			--numTrisInBin;
		}
		done = bin >= NUM_XFORMVERTS_TASKS;
		
		if(allBinsEmpty)
		{
			return;
		}

		vFloat4* xformedvPos = (vFloat4*)&xformedPos;

		// use fixed-point only for X and Y.  Avoid work for Z and W.
        vFxPt4 xFormedFxPtPos[3];
		for(int i = 0; i < 3; i++)
		{
			xFormedFxPtPos[i].X = ftoi_round(xformedvPos[i].X);
			xFormedFxPtPos[i].Y = ftoi_round(xformedvPos[i].Y);
			xFormedFxPtPos[i].Z = ftoi_round(xformedvPos[i].Z);
			xFormedFxPtPos[i].W = ftoi_round(xformedvPos[i].W);
		}

		// Fab(x, y) =     Ax       +       By     +      C              = 0
		// Fab(x, y) = (ya - yb)x   +   (xb - xa)y + (xa * yb - xb * ya) = 0
		// Compute A = (ya - yb) for the 3 line segments that make up each triangle
		VecS32 A0 = xFormedFxPtPos[1].Y - xFormedFxPtPos[2].Y;
		VecS32 A1 = xFormedFxPtPos[2].Y - xFormedFxPtPos[0].Y;
		VecS32 A2 = xFormedFxPtPos[0].Y - xFormedFxPtPos[1].Y;

		// Compute B = (xb - xa) for the 3 line segments that make up each triangle
		VecS32 B0 = xFormedFxPtPos[2].X - xFormedFxPtPos[1].X;
		VecS32 B1 = xFormedFxPtPos[0].X - xFormedFxPtPos[2].X;
		VecS32 B2 = xFormedFxPtPos[1].X - xFormedFxPtPos[0].X;

		// Compute C = (xa * yb - xb * ya) for the 3 line segments that make up each triangle
		VecS32 C0 = xFormedFxPtPos[1].X * xFormedFxPtPos[2].Y - xFormedFxPtPos[2].X * xFormedFxPtPos[1].Y;
		VecS32 C1 = xFormedFxPtPos[2].X * xFormedFxPtPos[0].Y - xFormedFxPtPos[0].X * xFormedFxPtPos[2].Y;
		VecS32 C2 = xFormedFxPtPos[0].X * xFormedFxPtPos[1].Y - xFormedFxPtPos[1].X * xFormedFxPtPos[0].Y;

		// Compute triangle area
		VecS32 triArea = B2 * A1 - B1 * A2;
		VecF32 oneOverTriArea = VecF32(1.0f) / itof(triArea);

		// Z setup
		VecF32 Z[3];
		Z[0] = xformedvPos[0].Z;
		Z[1] = (xformedvPos[1].Z - Z[0]) * oneOverTriArea;
		Z[2] = (xformedvPos[2].Z - Z[0]) * oneOverTriArea;

		// Use bounding box traversal strategy to determine which pixels to rasterize 
		VecS32 startX = vmax(vmin(vmin(xFormedFxPtPos[0].X, xFormedFxPtPos[1].X), xFormedFxPtPos[2].X), VecS32(tileStartX)) & VecS32(~1);
		VecS32 endX   = vmin(vmax(vmax(xFormedFxPtPos[0].X, xFormedFxPtPos[1].X), xFormedFxPtPos[2].X) + VecS32(1), VecS32(tileEndX));

		VecS32 startY = vmax(vmin(vmin(xFormedFxPtPos[0].Y, xFormedFxPtPos[1].Y), xFormedFxPtPos[2].Y), VecS32(tileStartY)) & VecS32(~1);
		VecS32 endY   = vmin(vmax(vmax(xFormedFxPtPos[0].Y, xFormedFxPtPos[1].Y), xFormedFxPtPos[2].Y) + VecS32(1), VecS32(tileEndY));

        // Now we have 4 triangles set up.  Rasterize them each individually.
        for(int lane=0; lane < numSimdTris; lane++)
        {
			// Extract this triangle's properties from the SIMD versions
            VecF32 zz[3];
			for(int vv = 0; vv < 3; vv++)
			{
				zz[vv] = VecF32(Z[vv].lane[lane]);
			}

			int startXx = startX.lane[lane];
			int endXx	= endX.lane[lane];
			int startYy = startY.lane[lane];
			int endYy	= endY.lane[lane];
		
			 // Incrementally compute Fab(x, y) for all the pixels inside the bounding box formed by (startX, endX) and (startY, endY) 
			VecS32 aa0(A0.lane[lane]);
			VecS32 aa1(A1.lane[lane]);
			VecS32 aa2(A2.lane[lane]);

			VecS32 bb0(B0.lane[lane]);
			VecS32 bb1(B1.lane[lane]);
			VecS32 bb2(B2.lane[lane]);

			VecS32 cc0(C0.lane[lane]);
			VecS32 cc1(C1.lane[lane]);
			VecS32 cc2(C2.lane[lane]);

			VecS32 aa0Inc = shiftl<1>(aa0);
			VecS32 aa1Inc = shiftl<1>(aa1);
			VecS32 aa2Inc = shiftl<1>(aa2);

			VecS32 bb0Inc = shiftl<1>(bb0);
			VecS32 bb1Inc = shiftl<1>(bb1);
			VecS32 bb2Inc = shiftl<1>(bb2);

			// Tranverse pixels in 2x2 blocks and store 2x2 pixel quad depths
			// contiguously in memory ==> 2*X
			// This method provides better perfromance
			int rowIdx = (startYy * SCREENW + 2 * startXx);

			VecS32 col = VecS32(startXx) + colOffset;
			VecS32 row = VecS32(startYy) + rowOffset;

			VecS32 sum0Row = aa0 * col + bb0 * row + cc0;
			VecS32 sum1Row = aa1 * col + bb1 * row + cc1;
			VecS32 sum2Row = aa2 * col + bb2 * row + cc2;

			for(int r = startYy; r < endYy; r += 2,
											rowIdx = rowIdx + 2 * SCREENW,
											sum0Row += bb0Inc,
											sum1Row += bb1Inc,
											sum2Row += bb2Inc)
			{
				// Compute barycentric coordinates 
				int idx = rowIdx;
				VecS32 alpha = sum0Row;
				VecS32 beta = sum1Row;
				VecS32 gama = sum2Row;

				for(int c = startXx; c < endXx; c += 2,
												idx += 4,
												alpha += aa0Inc,
												beta  += aa1Inc,
												gama  += aa2Inc)
				{
					//Test Pixel inside triangle
					VecS32 mask = alpha | beta | gama;
					
					// Early out if all of this quad's pixels are outside the triangle.
					if(is_all_negative(mask))
						continue;
					
					// Compute barycentric-interpolated depth
					VecF32 depth = zz[0];
					depth += itof(beta) * zz[1];
					depth += itof(gama) * zz[2];

					VecF32 previousDepthValue = VecF32::load(&pDepthBuffer[idx]);
					VecF32 mergedDepth = vmax(depth, previousDepthValue);
					depth = select(mergedDepth, previousDepthValue, mask);
					depth.store(&pDepthBuffer[idx]);
				}//for each column											
			}// for each row
		}// for each triangle
	}// for each set of SIMD# triangles
}